Driven Racing 420 Front Sprocket for Honda Grom and Monkey 125 (169-539)

Driven Racing EVO TECH 15 tooth front sprocket for Honda Grom and Monkey 125cc with 420 chain. This is a high quality, case hardened steel replacement sprocket.

Driven Honda Grom and Monkey 125 front sprockets for 420 chain is available in 15 tooth, which is the stock front sprocket size on the Honda Grom.

A few rules regarding gear ratios for sprockets are as follows:

• Drop teeth on front/add teeth to rear = increased torque, increased acceleration, wheelies, racetracks with short straights
• Add tooth on front/reduce teeth on rear = increased top end speed, open road cruising, lowers RPMs, better gas mileage, tracks with long straights
• 1 down on the front is like adding 3 teeth on the rear
• The bigger the rear sprocket, the lower the gearing and the faster the acceleration

Please click here to view our Gear Ratio Chart!

• Available in 15 Tooth
• Case Hardened
• Fits #420 Chain
• Inner Diameter (peak to peak): 14mm
• Inner Diameter (valley to valley): 17mm
• Thread Size: M6x1.00
• Made in USA!